It's a Dual Spark Ignition truck. It is solely for emissions purposes, and only results in causing the end user to spend TWICE as much when replacing plugs, wires, or DIS modules. Basically the passenger's side or exhaust side plugs fire after initial combustion to burn off exhaust gasses a little bit more.
Good move on the Sea Foam and air filter. How about an oil and filter change, tranny fluid and filter change, and check the rear diff fluid. Those can be done in a few hours on a nice day. I would also run a bottle of Lucas injector cleaner. Maybe even clean the MAF, IAT, IAC, and throttle body with electronics cleaner and carb cleaner respectively. How does the coolant look?
The Black Beast 5.0
Better to Have Horsepower and not Need it, than to Need it and not Have it!
2000 Ranger Sport - 5.0L V8 - 8.8 LS rear